Analytical Sciences
Online ISSN : 1348-2246
Print ISSN : 0910-6340
ISSN-L : 0910-6340
Volume 21 , Issue 7
Showing 1-34 articles out of 34 articles from the selected issue
Rapid Communications
Reviews
  • Jun KAWAI
    2005 Volume 21 Issue 7 Pages 733-735
    Published: 2005
    Released: November 18, 2005
    JOURNALS FREE ACCESS
    Radiative Auger spectra are weak X-ray emission spectra near the characteristic X-ray lines. Radiative Auger process is an intrinsic energy-loss process in an atom when a characteristic X-ray photon is emitted, due to an atomic many-body effect. The energy loss spectra correspond to the unoccupied conduction band structure of materials. Therefore the radiative Auger effect is an alternative tool to the X-ray absorption spectroscopy such as EXAFS (Extended X-ray Absorption Fine Structure) and XANES (X-ray Absorption Near Edge Structure), and thus it is named EXEFS (Extended X-ray Emission Fine Structure). By the use of a commercially available X-ray fluorescence spectrometer or an electron probe microanalyzer (EPMA), which are frequently used in materials industries, we can obtain an EXEFS spectrum within 20 min. The radiative Auger effect, as an example, demonstrates that the study on atomic many-body effects has become a powerful tool for crystal and electronic structure characterizations. The EXEFS method has already been used in many industries in Japan. Reviews about the applications and basic study results on the radiative Auger effect are reported in this paper.
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  • T. PAPP, A. T. PAPP, J. A. MAXWELL
    2005 Volume 21 Issue 7 Pages 737-745
    Published: 2005
    Released: November 18, 2005
    JOURNALS FREE ACCESS
    There is a large scatter in the results of X-ray analysis with solid-state detectors suggesting methodological origin. In order to improve the methodology, detector response functions have been investigated by many researchers and analysts. This was necessary as the departure of the response function of some detector-signal processing electronics from the normally assumed Gaussian line shape can exceed 100% in area. Several detector models have been proposed to improve understanding and establish a firm basis for quantitative work. After reviewing some contradictory results, we describe a signal processor that offers quality assurance, by producing two spectra for each measurement. One is the normal spectrum of accepted events, while the second spectrum contains all of the rejected events. For each measurement, therefore, all X-ray events are recorded, enabling quality control. In addition to this improvement, the digital signal processor of Cambridge Scientific, Canada, delivers a high throughput rate, excellent resolution, decreased low energy tailing and a line shape justified by the physics of the detector. Comparative measurements are presented to demonstrate the improved rejection of background from gamma rays as well as a significant improvement in pile-up recognition. The rejected events spectrum gives insight into the origin of the response function, which suggests that the flat plateau of the frequently used Hypermet function, normally attributed to detector dead layers, originates from pile-up with the low energy noise events. A detailed analysis demonstrates how the relative intensities of the X-ray lines can change in a varying noise environment, thus potentially explaining the unacceptable large scatter in the experimental data currently found in the literature. The comparison of the accepted and rejected events adds the possibility of monitoring the electronic efficiency of signal recognition that has generally been ignored in this field.
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Original Papers
  • M. L. CARVALHO, A. C. PIMENTEL, B. FERNANDES
    2005 Volume 21 Issue 7 Pages 747-750
    Published: 2005
    Released: November 18, 2005
    JOURNALS FREE ACCESS
    In this work we studied and compared the metal uptake in edible mushrooms (Lepiota procera, Boletus badius, Boletus edulis, Tricholoma equestry, Lactarius deliciosus, Cantarelus tubalformis and Cantarelus edulis), relative to sampling sites submitted to different pollution conditions: car traffic, soil pollution due to pesticides and fertilizers used in old vineyards, and incineration of hospital waste. Soil was also collected in some places, and its content was correlated to the corresponding one in some mushrooms species. All samples, without any chemical treatment, were analyzed by an X-ray fluorescence set-up. This technique is based on a monochromatic X-ray beam ionizing the atoms of the sample. Following this ionization, the emitted radiation is characteristic of the element, allowing its identification and quantification. Vineyards are normally submitted to very high amounts of sulfating, containing high copper concentrations. This metal is accumulated on the soil, and can be up-taken by vegetation. Very high levels of Fe and Cu were found in Lepiota procera species in old vineyards. Zinc was found to be always higher than Cu by factors ranging from 1.5 to 8 in clean wood taken as a reference for the whole analyzed species, while in old vineyards the ratio Zn/Cu reach 0.25 for Lepiota procera. This is correlated to the soil content for both elements. In addition, pollution induced by car traffic was checked in some samples, collected in the proximity of highways. Pb was the main contaminant in these areas, and presenting values 10 times higher than the corresponding ones in sites not submitted to pollution, for some species. Mushrooms contamination due to incineration of hospital waste was also studied, but we did not observe any contamination involving heavy metals in the several analyzed species around these areas. This is in agreement with what was expected, taking into account that hospital waste is mostly organic and, in principle, no heavy metals would be observed.
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  • Graciela CUSTO, Susana BOEYKENS, L. DAWIDOWSKI, L. FOX, D. GÓME ...
    2005 Volume 21 Issue 7 Pages 751-756
    Published: 2005
    Released: November 18, 2005
    JOURNALS FREE ACCESS
    This work describes a sampling strategy that will allow the use of portable EDXRF (energy dispersive X-ray fuorescence) instruments for “in situ” soil analysis. The methodology covers a general approach to planning field investigations for any type of environmental studies and it was applied for a soil characterization study in the zone of Campana, Argentina, by evaluating data coming from an EDXRF spectrometer with a radioisotope excitation source. Simulating non-treated sampled as “in situ” samples and a soil characterization for Campana area was intended. “In situ” EDXRF methodology is a powerful analytical modality with the advantage of providing data immediately, allowing a fast general screening of the soil composition.
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  • M. K. TIWARI, S. R. NAIK, G. S. LODHA, R. V. NANDEDKAR
    2005 Volume 21 Issue 7 Pages 757-762
    Published: 2005
    Released: November 18, 2005
    JOURNALS FREE ACCESS
    Incident primary beam divergence is a source of systematic error in X-ray standing wave (XSW) characterization of single and multilayer thin films. Primary beam divergence significantly alters the XSW profile of a layered material and can lead to large errors when used with higher excitation energies. The present study suggests that when one uses Mo-Kα excitation, the primary beam divergence should be in range of 0.0050. On the other hand, in the case of Cu-Kα excitation, primary beam divergence can be relaxed up to 0.010.
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  • Cristina VÁZQUEZ, Graciela CUSTO, Laura DAWIDOWSKI, Darí ...
    2005 Volume 21 Issue 7 Pages 763-767
    Published: 2005
    Released: November 18, 2005
    JOURNALS FREE ACCESS
    Multielemental composition and morphology of particulate matter samples were examined to detect the presence of two potential responsible pollutant emitters at four sites impacted during a pollution episode in the City of Campana, Argentina. Coke and smoke black are the main constituents associated to the industrial plants that were considered, a priori, as responsible pollutant emitters. Wavelength dispersive X-ray fluorescence (WDXRF) was employed for the analysis of metals in samples coming from both, suspected sources and four sites. On the basis of multielemental composition profiles, a screening analysis was undertaken for exploring similarities among sources and sample sites adopting the average concentration profile of the crustal rock as soil surrogate. Particle morphology was studied by scanning electron microscopy (SEM) in source samples and in those environmental samples selected through the screening analysis. Two types of collected samples were analyzed: 1) those with composition profiles closer to the potential sources and 2) those closer to the cluster rock. This strategy was adequate to identify the responsible source of the contamination episode.
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  • Masaki TAKAOKA, Satoshi FUKUTANI, Takashi YAMAMOTO, Masato HORIUCHI, N ...
    2005 Volume 21 Issue 7 Pages 769-773
    Published: 2005
    Released: November 18, 2005
    JOURNALS FREE ACCESS
    Only limited information is available about the behavior of antimony (Sb) in contaminated soils. However, understanding the behavior of Sb in contaminated soils is important, because the toxicity or solubility of this element depends on its chemical state. In this study, we investigated the levels of Sb and the chemical forms of Sb in the soil around a smelter using X-ray absorption fine structure (XAFS) spectra. The highest Sb concentration in the contaminated soil was 2900 mg/kg dry soil. According to Sb-K edge X-ray absorption near edge (XANE) spectra, the Sb in the soil was in the form of Sb(V) compounds. The similarity of extended XAFS (EXAFS) spectra suggests that Sb speciation was independent of the sampling site, which indicates that Sb or Sb2O3 emitted from the smelter was converted into Sb(V) compounds in the soil.
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  • Shinichi SUZUKI, Yasuhiro SUZUKI, Hikoto OHTA, Masaaki KASAMATSU, Tosh ...
    2005 Volume 21 Issue 7 Pages 775-778
    Published: 2005
    Released: November 18, 2005
    JOURNALS FREE ACCESS
    Thirteen arsenous acid samples of known origins and refining methods were collected. Each sample was subjected to quantitative analysis of any impurity elements present using synchrotron radiation X-ray fluorescence spectrometry (SR-XRF) and inductively coupled plasma-atomic emission spectrometry (ICP-AES). The trace elements selected were Sn, Sb and Bi for the reasons that they were considered not to be changed by their circumstances and that they showed high sensitivity to SR-XRF. These results obtained by both methods were compared and the correlation between these two methods was determined. The quantification of trace impurities obtained by SR-XRF using As as an internal standard showed good agreement with the results obtained by ICP-AES. The discrimination of refining method became possible by the comparison of these impurities' contents measured with non-destructive SR-XRF using several arsenous acid particles.
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  • Junichi TSUJI, Manabu FUJITA, Yuichi HARUYAMA, Kazuhiro KANDA, Shinji ...
    2005 Volume 21 Issue 7 Pages 779-781
    Published: 2005
    Released: November 18, 2005
    JOURNALS FREE ACCESS
    The Li 1s XPS (X-ray Photoelectron Spectroscopy) spectra of LiMn2O4, which is one of the major positive-electrode materials in lithium-ion rechargeable batteries, and MnO2 as a reference material, were measured by a laboratory-type XPS spectrometer. The Li 1s peak was not observed in the spectra excited by the Mg Kα line (1253.6 eV), because the Li 1s peak overlapped the background of the Mn 3p peak of LiMn2O4. The photoionization cross section of Mn 3p was larger than that of Li 1s for Mg Kα excitation. Therefore, the XPS measurement of LiMn2O4 by soft X-ray synchrotron excitation was carried out at beamline BL-7B on NewSUBARU synchrotron facility. Excitation energies of 110, 120, 130, 140, 150 and 151.4 eV were selected. The Li 1s peak was clearly observed in these XPS spectra. In order to investigate the excitation energy dependence, the area ratio of the Li 1s and Mn 3p peaks in the XPS spectra was plotted against the excitation energy. As a result, when the excitation energy was 110 eV, the area ratio had the maximum value.
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  • Hideshi ISHII, Jun KAWAI
    2005 Volume 21 Issue 7 Pages 783-784
    Published: 2005
    Released: November 18, 2005
    JOURNALS FREE ACCESS
    X-ray absorption spectral (XAS) analysis is performed with a combination of a 9 V dry electric battery X-ray generator and a portable Si PIN X-ray detector. The calcium K edge (4.0 keV) in paper is measured with a grazing incidence geometry, which suppressed the artifact due to the Kα X-ray fluorescence peak at 3.5 keV. The 9 V dry battery X-ray emitter is useful for portable XAS measurements.
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  • Masaaki KASAMATSU, Yasuhiro SUZUKI, Toshio NAKANISHI, Osamu SHIMODA, Y ...
    2005 Volume 21 Issue 7 Pages 785-787
    Published: 2005
    Released: November 18, 2005
    JOURNALS FREE ACCESS
    Small particles of gold foil detached from an indoor decoration might be important evidence to associate a suspect with a crime scene. We have investigated the application of elemental analysis using synchrotron radiation X-ray fluorescence spectrometry to discriminate small particles of gold foil. Eight kinds of gold foil samples collected in Japan were used in the experiments. As a result of synchrotron radiation X-ray fluorescence spectrometry, only two elements, gold and silver, were detected from all gold foil samples. The intensity ratios of AgKα/AuLα showed good correlation with the content ratios of Ag/Au. The variation of intensity ratio within a same sample was sufficiently small compared with those of different samples. Therefore the comparison of this intensity ratio can be an effective method to discriminate small particles originating from different types of gold foil.
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  • Hironori OHASHI, Hiroyuki EZOE, Yoshihiro OKAUE, Yasuhiro KOBAYASHI, S ...
    2005 Volume 21 Issue 7 Pages 789-793
    Published: 2005
    Released: November 18, 2005
    JOURNALS FREE ACCESS
    The effect of UV (ultraviolet) irradiation on the adsorption of Au(III) ions on manganese dioxide and their reduction to Au(0) (gold with 0 valence state) was investigated using XPS (X-ray photoelectron spectroscopy) and 197Au Mössbauer spectroscopy. The UV irradiation accelerated the adsorption and the reduction. From the fact that the proportion of Au(0) estimated from Au 4f XPS spectra for surface analysis was significantly smaller than that from 197Au Mössbauer spectra for bulk analysis, we deduced that Au(0) was interpenetrated to the inside of manganese dioxide (into deeper places than about 30 Å) where XPS is impossible to detect. The content of surface hydroxyl groups on manganese dioxide also increased due to the UV irradiation. The relationship between the charge in the content of hydroxyl groups and the interpenetration of Au(0) is discussed.
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  • Joëlle BLANC, Sébastien POPULAIRE, Loïc PERRING
    2005 Volume 21 Issue 7 Pages 795-798
    Published: 2005
    Released: November 18, 2005
    JOURNALS FREE ACCESS
    A simple method for the rapid identification of inorganic salts used as raw materials during food production has been established using energy dispersive X-ray fluorescence (EDXRF). Intensities of Na, Mg, P, S, Cl, K, Ca, Mn, Fe, Cu, Zn Kα peaks have been measured. The treatment and comparison of the respective intensities allowed a rapid identification of inorganic salts. Two different methods of data treatment have been tested: K nearest neighbours (KNN) and centroids. Using cross validation on a database containing 140 samples representing 31 classes, a total of 98% of samples were well identified.
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  • Kouichi TSUJI, Tetsuya EMOTO, Yosuke NISHIDA, Eiichiro TAMAKI, Yoshiku ...
    2005 Volume 21 Issue 7 Pages 799-803
    Published: 2005
    Released: November 18, 2005
    JOURNALS FREE ACCESS
    Grazing-exit x-ray fluorescence (GE-XRF) and micro x-ray fluorescence (μ-XRF) methods were applied to chemical microchips as a detection method. Since an energy-dispersive x-ray detector was used, the simultaneous detection of multiple elements was possible. An analyzing region was especially designed on the microchip so that a sample solution could be dried and concentrated in a suitable area corresponding to the size of the primary x-ray beam. Finally, it was confirmed that both analytical methods could be combined well for use with a microchip. In GE-XRF, the background intensity in the XRF spectrum was reduced at grazing-exit angles. In addition, a good relationship between the x-ray fluorescence intensities and the concentrations of standard solutions that were introduced into the microchip was obtained. This indicates that the GE-XRF method is feasible for trace elemental analysis in chemical microchip systems. In μ-XRF, an attempt was made to concentrate and dry the analyte within a small analyzing region. The preliminary results indicated that the μ-XRF method could be applied for the analysis of microchips.
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  • Shuji MATSUO, Nahomi SAKAGUCHI, Hisanobu WAKITA
    2005 Volume 21 Issue 7 Pages 805-809
    Published: 2005
    Released: November 18, 2005
    JOURNALS FREE ACCESS
    Titanium K-edge X-ray absorption near-edge structure (XANES) spectroscopy is used to examine the local Ti environments in the sol, gel, and xerogels of titanium oxide prepared by a sol-gel method. The xerogels were prepared by heat treatment at 200, 300, 400, 500, and 600°C (denoted xero-200, xero-300, xero-400, xero-500, and xero-600), and the xerogels were doped with Fe(II), Ni(II), and Cu(II) ions (xero-Fe, xero-Ni, and xero-Cu). The local structures of the samples are compared using the pre- and post-edge features of the XANES spectra. Further analysis of the pre-edge features using Gaussian functions provides the energy and height of each peak, and the intensity ratios between peaks. Based on the resulting data, the samples can be classified into three groups: a weak Ti-Ti interaction group, an anatase-like structure group, and an anatase group. The sol, gel, xerogel, and xero-Ni are in the weak Ti-Ti interaction group, and the xero-200, xero-Fe, and xero-Cu are in the anatase-like structure group. The remaining samples are in the anatase group.
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  • Pavel KARIMOV, Jun KAWAI, Ernst Z. KURMAEV
    2005 Volume 21 Issue 7 Pages 811-813
    Published: 2005
    Released: November 18, 2005
    JOURNALS FREE ACCESS
    A numerical simulation was done to check the possibility of using planar C/C/C multilayers with density contrast 0.2 and 0.7 g/cm3 as an X-ray waveguide. After an optimization procedure, suitable waveguide layer thicknesses were found which provide a high degree of resonant standing wave field intensity enhancement in the core layer at incident beam energy of 13 keV. The obtained results were compared with those of the Mo/Be/Mo waveguide, whose high waveguiding capability at the same energy value was reported in the 1990s. The comparison shows that standing wave field intensity resonant enhancement provided by C/C/C planar multilayers is very high and, consequently, a guided beam can be well detected.
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  • Kenichi NAKAYAMA, Toshihiro NAKAMURA
    2005 Volume 21 Issue 7 Pages 815-822
    Published: 2005
    Released: November 18, 2005
    JOURNALS FREE ACCESS
    Major and trace elements (Na, Mg, Al, Si, P, K, Ca, Ti, Mn, Fe, Rb, Sr, Y, Zr, La, Ce, Pr, Nd, Sm, Gd, Dy, Th and U) in igneous rocks were assayed with fused lithium borate glass beads using X-ray fluorescence spectrometry. Low dilution glass beads, which had a 1:1 sample-to-flux ratio, were prepared for determination of rare earth elements. Complete vitrification of 1:1 mixture required heating twice at 1200°C with agitation. Extra pure reagents containing determinants were used for calibrating standards instead of the rock standard. The calibration curves of the 23 elements showed good linearity. Furthermore, the lower limits of detection corresponding to three times the standard deviation for blank measurements were 26 mass ppm for Na2O, 6.7 for MgO, 4.5 for Al2O3, 4.5 for SiO2, 18 for P2O5, 1.1 for K2O, 4.0 for CaO, 3.9 for TiO2, 1.6 for MnO, 0.8 for Fe2O3, 0.5 for Rb, 0.2 for Sr, 0.4 for Y, 0.5 for Zr, 3.3 for La, 6.5 for Ce, 2.7 for Pr, 2.1 for Nd, 1.7 for Sm, 0.7 for Gd, 2.7 for Dy, 0.5 for Th, and 0.6 for U. Using the present method, we determined the contents of these 23 elements in four rhyolitic and granitic rocks from Japan.
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  • Vasilios HATZISTAVROS, Pavlos KOULOURIDAKIS, Nikolaos KALLITHRAKAS-KON ...
    2005 Volume 21 Issue 7 Pages 823-826
    Published: 2005
    Released: November 18, 2005
    JOURNALS FREE ACCESS
    Selective membranes containing a few micrograms of various complexing reagents in a polyvinyl chloride (PVC) matrix were produced in order to determine low uranium concentrations in water. The membranes were produced on the surfaces of quartz glasses, and immersed in water solutions containing uranium salts (5 - 50 ng/mL). By the end of the equilibration time, the membranes were left to dry and analyzed based on the total reflection X-ray fluorescence. The effects of the complexing agents and their mass proportions added in the membranes were studied. The combination of the complexing reagents dithizone and thiourea gave the best result. The minimum detection limit was measured to be equal to 0.8 ng/mL.
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  • Masayasu KURAHASHI, Jun MIZUTANI, Akiharu HIOKI
    2005 Volume 21 Issue 7 Pages 827-832
    Published: 2005
    Released: November 18, 2005
    JOURNALS FREE ACCESS
    A new reliable analytical method, “Monochromatic X-ray Excitation X-ray Fluorescence Spectrometry”, has been proposed. For validating the method, trace elements in sediment certified reference materials were determined. In the method X-ray fluorescence spectra are measured for specimens and pure metals; in addition the mass-attenuation coefficients of the specimens for various X-ray wavelengths are also measured. The data are analyzed by the fundamental parameter method and the uncertainty of the analysis is evaluated. The obtained results were in satisfactory agreement with the certified values within their uncertainties. This method will be applicable to the certification of reference materials, in the field of which reliable results with uncertainty statements are required.
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  • S. THANGADURAI, J. T. ABRAHAM, A. K. SRIVASTAVA, M. NATARAJA MOORTHY, ...
    2005 Volume 21 Issue 7 Pages 833-838
    Published: 2005
    Released: November 18, 2005
    JOURNALS FREE ACCESS
    X-ray powder diffraction (XRD) data for eight β-lactam viz., ampicillin sodium, ampicillin trihydrate, penicillin G procaine, benzathine penicillin, benzyl penicillin sodium, cefalexin, cefotaxime sodium and ceftriaxone sodium; three tetracyclines viz., doxycycline hydrochloride, oxytetracycline dihydrate and tetracycline hydrochloride; and two macrolide viz., azithromycin and erythromycin estolate antibiotic drugs were obtained using a powder diffractometer. The drugs were scanned from Bragg angles (2 θ) of 10° to 70°. The obtained data were tabulated in terms of the lattice spacing (Å) and relative line intensities (I/II). This new information may be useful for identifying these drugs from confiscated materials, which has been frequently encountered in forensic laboratories.
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  • Yoichi TANAKA, Yuji TANIGUCHI, Daisaku TANAKA, Masatoshi TOYODA, Hides ...
    2005 Volume 21 Issue 7 Pages 839-843
    Published: 2005
    Released: November 18, 2005
    JOURNALS FREE ACCESS
    The Kosa (yellow sand) aerosol affects the global environment as well as human health because it migrates from the interior of China to other areas, absorbing various atmospheric elements. Investigation into individual Kosa aerosol particles, which are submicroscopic to several tens of micrometers in diameter, is required to resolving the issue. We installed a scanning electron microscope (SEM) equipped with an energy dispersive X-ray spectrometer (EDX) on a synchrotron radiation (SR) beam line and introduced the SR beam into the SEM chamber for combinatorial application of SEM-EDX and SR X-ray fluorescence (SR-XRF) spectrometry to individual particles. It should be noted that detailed topographic observation by SEM and sensitive elemental analysis by SR-XRF, both crucial for individual particle measurement but which previously had to be carried out separately, were jointly performed inside the SEM chamber in this setup. Here, we show that SR-XRF results, in conjunction with SEM images, contributed toward resolving individual particle dispositions. Atmospheric sulfur primarily adheres to calcium in the aerosol particles and the particle surface roughens as a consequence of the chemical reaction between the two elements.
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  • David HELLIN, Annelies DELABIE, Riikka L. PUURUNEN, Peter BEAVEN, Thie ...
    2005 Volume 21 Issue 7 Pages 845-850
    Published: 2005
    Released: November 18, 2005
    JOURNALS FREE ACCESS
    In future microelectronic devices, SiO2 as a gate dielectric material will be replaced by materials with a higher dielectric constant. One such candidate material is HfO2. Thin layers are typically deposited from ligand-containing precursors in chemical vapor deposition (CVD) processes. In the atomic layer deposition (ALD) of HfO2, these precursors are often HfCl4 and H2O. Obviously, the material properties of the deposited films will be affected by residual ligands from the precursors. In this paper, we evaluate the use of grazing incidence- and total reflection-X-ray fluorescence spectrometry (GI-XRF and TXRF) for Cl trace analysis in nanometer-thin HfO2 films deposited using ALD. First, the results from different X-ray analysis approaches for the determination of Hf coverage are compared with the results from Rutherford backscattering spectrometry (RBS). Next, we discuss the selection of an appropriate X-ray excitation source for the analysis of traces within the high- κlayers. Finally, we combine both in a study on the accuracy of Cl determinations in HfO2 layers.
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  • Zi-Tao JIANG, Jimmy C. YU, Ho-Yan LIU
    2005 Volume 21 Issue 7 Pages 851-854
    Published: 2005
    Released: November 18, 2005
    JOURNALS FREE ACCESS
    A sensitive method for the preconcentration and determination of trace amounts of Co, Cu and Zn by energy-dispersive X-ray fluorescence spectrometry (EDXRF) has been developed. The method is based on the fact that 4-(2-pyridylazo)-resorcinol (PAR) loaded Dowex anion-exchange resin (PAR-resin) can effectively adsorb Co, Cu and Zn at pH 9.0 to form PAR-metal complexes. The detection limits for Co, Cu and Zn were 1.53, 0.31 and 0.21 ppb, respectively. The precisions for five replicate measurements of the three metals were 3.4, 2.7 and 2.1% RSD, and the calibration curves were linear up to 75 µg with correlation coefficients of 0.9975, 0.9980 and 0.9985, respectively. The method was successfully applied for the simultaneous determination of Co, Cu and Zn in seawater samples at ppb levels.
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  • Yasuhiro SUZUKI, Masaaki KASAMATSU, Shinichi SUZUKI, Toshio NAKANISHI, ...
    2005 Volume 21 Issue 7 Pages 855-859
    Published: 2005
    Released: November 18, 2005
    JOURNALS FREE ACCESS
    Measurements of the refractive index (RI) and elemental analysis using synchrotron radiation X-ray fluorescence spectrometry (SR-XRF) were applied to the forensic discrimination of sheet-glass samples from different origins. The refractive index was calculated from the matching temperature at which the glass fragments became invisible in silicone oil. Fragments smaller than 1 mm in maximum diameter were taken from each of 11 sheet glasses and subjected to analysis by SR-XRF. The XRF spectrum of these samples indicated that a comparison of 6 elements (Ca, Fe, Sr, Zr, Ba and Ce) was useful for the discrimination of sheet glasses. Cluster analysis was performed using 33 sets of SR-XRF data obtained by triplicate measurements for the 11 glasses. Comparing 528 pairs among 33 samples, 515 pairs could be correctly discriminated. The number of indistinguishable pairs could be reduced from 36 to 4 by comparing the SR-XRF data. Elemental analysis by SR-XRF could provide small glass fragments with a more evidential value than the solely measurement of only RI, through a significant improvement of the discrimination capability.
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  • Tokuzo KONISHI, Toshio TSUBATA, Masaoki OKU, Yanko M. TODOROV, Masaki ...
    2005 Volume 21 Issue 7 Pages 861-864
    Published: 2005
    Released: November 18, 2005
    JOURNALS FREE ACCESS
    High-resolution the Mn Kα1 X-ray fluorescence spectra (HRXRF) were measured for a variety of manganese compounds, the oxidation number (valence) of which was from II to VII. Plots of the valence against the full width at half maximum (FWHM) and the chemical shift of the Kα1 X-ray fluorescence spectra give a curve and a liniar relation, respectively. The coefficient of correlation (R2) for the latter plot was 0.989 between valency II and VII. More excellent linearlity from III to IV was obtained with R2 = 0.995, which enabled us to determine the oxidation number of manganese atom in a nickel ion doped spinel structure, LiMn2O4 (LiNixMn2-xO4, with 0.2 < x < 0.42). From the valence of manganese ion obtained from HRXRF, the oxidation number of nickel ion is concluded to be divalent.
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  • Jun KAWAI, Michiharu OHTA, Tokuzo KONISHI
    2005 Volume 21 Issue 7 Pages 865-868
    Published: 2005
    Released: November 18, 2005
    JOURNALS FREE ACCESS
    The nickel Kα spectra of oxides, halides (NiF2, K2NiF6, NiCl2, NiBr2), complex compounds, and metal are measured with two different double-crystal X-ray fluorescence spectrometers. The peak shifts and line width changes due to the changes in the chemical states are reported. High reproducibility has been shown for the chemical shift and line width measurements. The DV-Xα molecular orbital calculation at the ground and the 1s-1 hole states was performed to prove that the chemical effect originats from the charge-transfer mechanism.
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  • Wakako ARAKI, Kaoru MIZOROKI, Mitsuhiro OKI, Miyuki TAKENAKA
    2005 Volume 21 Issue 7 Pages 869-872
    Published: 2005
    Released: November 18, 2005
    JOURNALS FREE ACCESS
    The μ-EDXRF (energy dispersive X-ray fluorescence) method was applied to the screening of Pb in micrometer-area samples, such as a Cu contact in electrical components that had been coated by Pb-free Sn-Ag-Cu solder. The reliability of the screening method was evaluated by a comparison with a scanning electron microscope (SEM) observation and a precious chemical analysis method of inductively coupled plasma mass spectrometry (ICP-MS). Some factors that affect the testing reliability, such as the thickness of the solder, the segregation of Pb and Ag, etc. were found by SEM observations. By adjusting some calculation parameters, screening of the micrometer area (0.1 mm) was performed using the fundamental parameter (FP) method for a thin film in conjunction with μ-EDXRF. The measurement error ranged by 25% for the thin film-FP method. The resulted detection limit was 0.04 wt% for Pb, depending on the solder thickness. This method can be successively applied for quality control to check the purity of a Pb-free Sn-Ag-Cu solder coating in electrical components.
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  • Hagen STOSNACH
    2005 Volume 21 Issue 7 Pages 873-876
    Published: 2005
    Released: November 18, 2005
    JOURNALS FREE ACCESS
    Total reflection X-ray fluorescence (TXRF) analysis is an established technique for trace-element analysis in various types of samples. Though expensive large-scale systems restricted the applications in the past, in this study the capability of a benchtop system for trace elemental analysis is reported. The suitability of this system for the mobile on-site analysis of heavy metal contaminated soils and sediments is reported as well as the possibilities and restrictions of TXRF for additional applications, including trace-element analysis of water, glass and biological samples.
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  • Nobuya INADA, Kuniko MAEDA, Jun KAWAI
    2005 Volume 21 Issue 7 Pages 877-880
    Published: 2005
    Released: November 18, 2005
    JOURNALS FREE ACCESS
    Terasawa reported strong X-ray emission from charged-up insulators, and proposed an X-ray production device only using the electrification. We constructed a similar device and studied the conditions of X-ray emission. It was shown that X-rays could be produced without supplying electrons from a filament.
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  • Hiroaki MURAKAMI, Ryoichi ONO, Atsuhiko HIRAI, Yoshinori HOSOKAWA, Jun ...
    2005 Volume 21 Issue 7 Pages 881-884
    Published: 2005
    Released: November 18, 2005
    JOURNALS FREE ACCESS
    A compact X-ray emission instrument is made, and the X-ray spectra are measured by changing the applied electric potential. Strong soft X-rays are observed when evacuating roughly and applying a high voltage to an insulator settled in this device. The X-ray intensity is higher as the applied voltage is increased. A light-emitting phenomenon is observed when this device emits X-rays. The present X-ray emitter is made of a small cylinder with a radius of 20 mm and a height of 50 mm. This X-ray generator has a potential to be used as an X-ray source in an X-ray fluorescence spectrometer.
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  • Ari IDE-EKTESSABI, MARIONA RABIONET
    2005 Volume 21 Issue 7 Pages 885-892
    Published: 2005
    Released: November 18, 2005
    JOURNALS FREE ACCESS
    The present paper focuses on the analysis of trace metallic elements and their role in neurodegenerative disorders. The use of synchrotron radiation microbeams allows investigation of pathological tissues from Alzheimer's disease, Parkinson's disease and Amyotrophic lateral sclerosis cases in a nondestructive manner and at cellular level. By employing X-ray absorption near edge structure (XANES) technique, the chemical state of the investigated elements can be determined, while energy-selective X-ray fluorescence spectroscopy provides the spatial distribution of each element in each oxidative state selectively. The investigated tissues (derived from human, monkey and mouse specimens) show distinct imbalances of metallic elements such as Zn and Cu as well as Fe2+/Fe3+ redox pair, which point to oxidative stress as a crucial factor in the development or progress of these neurodegenerative diseases.
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